Four ichneumonid species, Itoplectis conquisitor (Say), Pimpla pedalis Cress., Theronia atalantae (Poda), and Theronia hilaris (Say), were seen attacking the gypsy moth, Porthetria dispar (L.), in the Town of Glenville, Schenectady County, New York. These species stung and killed many more host pupae than they successfully parasitized (success here being measured by the development of an ichneumonid offspring within the host). The ratio between the total number of hosts stung by ichneumonids and the number of ichneumonid offspring emerging was different for each of the three primary ichneumonids studied, ranging from 4 to 1 for T. atalantae to more than 200 to 1 for I. conquisitor.

The sarcophagids associated with the gypsy moth, although apparently parasitic, are largely scavengers. Their attacks almost always follow those of ichneumonids. Since the sting by an ichneumonid kills the host but is not always discernible, the number of pupae containing sarcophagid larvae has been used to, indicate the true effects of ichneumonids on the host population.

The new tribe Athyreini is established in the subfamily Geotrupinae, family Scarabaeidae. The genus Athyreus MacLeay is delimited and three new genera, Pseudoathyreus, Parathyreus and Neoathyreus, are proposed.

The structure and position of the spiracles in Sitophilus granarius and Tribolium confusum adults was studied. On the basis of this an attempt was made to explain the differences in water loss from these two species under reduced pressure. It was concluded that the spiracular structure combined with the inflation of the body under very low pressures, can account for the apparently anomalous water loss results.

At least 25 species of Carabidae were caught in pitfall traps in a DDT-sprayed Ontario peach orchard, the commonest being Pterostichus melanarius (Ill.). Harpalus pennsylvanicus (Dej.), Agonoderus lecontei Chd., Amara (Curtonotus) pennsylvanica Hayw., Anadaptus sanctaecrucis (F.) and Anisodactylus rusticus Say. Fewer P. melanarius were caught in plots where foliar sprays of DDT were used most recently, but a rather large and varied population of carabids persisted in all plots despite the application of DDT for as long as ten years.

Before atten~pting to determine the nutritional requirements of Rhodnius prelixus Stål, a blood-feeding reduviid bug, it was necessary to build a feeding apparatus that would permit the insects to feed normally on various artificial diets. Since it was expected that large numbers of animals would have to be fed individually, practical considerations demanded that the feeding apparatus be easy to service and maintain. Some of the experimental diets would be extremely expensive and radioactive and consequently an apparatus that would permit the use of small volumes of diet was required.

Spray tower application of DDT in fuel oil at 0.2 lb. DDT/acre, proved to be highly toxic to the larvae of the western hemlock looper. Tolerance to DDT appeared to vary directly with larval age. Phosphamidon applied in aqueous solution to hemlock foliage showed a high order of contact and systemic toxicity to larvae placed on the treated foliage.

The cottony scale attacking the peach in Ontario is apparently the European species Pulvinaria vitis (L.) and may have been introduced to North America prior to 1897. It is thelytokous and has only one generation per year. The partly grown, adult female overwinters on the bark of its host. The eggs, laid about mid-May, are enclosed in a white, felt-like ovisac that is secreted by submarginal glands in the ventral region of the scale's body. The eggs, which on peach averaged about 4,000 per female, were laid over a relatively short period when the temperature was 14 °C. or higher. Eggs began to hatch after about 200 day degrees above 10 °C. Increasing the temperature increased the rate of hatching, but no close correlation was found between the rate of hatching and the average daily temperature during the hatching period.

The newly emerged nymphs were both phototactic and photokinetic, and their establishment on the host plant was affected by several factors including light, humidity, and air movement. For a given set of conditions there appeared to be a maximum number of nymphs that could become established per unit area of host. P. vitis was dispersed by wind at any stage when it was active, but especially at the early crawler stage.

Growth of the scales was discontinuous with varying periods when no growth took place. There were three moults: the first 12 to 18 days after hatching; the second 28 to 36 days; and the third 56 to 93 days. At ecdysis only the cuticle of the ventral surface and the appendages was shed. Movement of the scales on the host plant was particularly frequent till the first moult, but some movement took place throughout the summer and early fall except for a period in late August and early September. Only a small percentage of the scales reached the bark from the leaves, probably due to random movement.

Feeding appeared to be discontinuous with periods of days when no feeding took place. The scales fed on the phloem, but on twigs the stylets penetrated as far as the xylem and destroyed the cambium in the feeding area.

Though parasites and predators exist in the area and appeared to be capable of exercising a large measure of control, the spray programs used in the orchards held them to relatively small numbers. At least one species of parasite was almost absent from sprayed orchards.

Nepytia freemani, a new species attacking Douglas fir in British Columbia, is described and compared with its near relatives.

Investigations into the causal organism of late fall browning in Wisconsin disclosed an undescribed species of gall midge. The taxonomic description and a summary statement of the life history are presented.

Adults of Drino bohemica Mesn., a tachinid parasite, learned to associate the movement of a part of their cage with the presence of host larvae. The parasites became habituated to an artist’s brush. Learning was retained for a period varying from a few hours to a few days. There were differences in the ability of groups of parasites to learn and to retain learning. The ability of the parasite to learn a new clue for use in locating hosts would interact with other factors that influence host-finding and host selection.

The population dynamics of the gypsy moth, Porthetria dispar (L.), are being studied on 10 sites in the Town of Glenville, New York. This paper discusses the role of disease and a condition here termed “desiccation” in the dynamics of these populations during a 4-year period, 1958-1961 inclusive.

The term “desiccation” refers to dead pre-pupae that appeared shriveled, and were stiff to the touch, and which had a solid mass of food in their gut. The incidence of desiccation among pre-pupae was closely related to the number of eggs per egg mass produced at the end of the generation (a measure of relative insect density).

Disease incidence among larval gypsy moth populations was directly related to insect density. Disease incidence was also related to site conditions, with higher mortality occurring in wet sites.

When larval populations reached high densities, they always declined from the dense level within a few generations. These declines ranged from a sudden drastic reduction to a much more gradual decline. The former was preceded by virtual food exhaustion, while the latter was not usually preceded by exhaustion of the food supply.

Disease and desiccation were primary factors in producing the sudden type of population reduction noted above. Pathogens may also play an important part in the more gradual type of decline, but this point remains to be clarified.

During 1961 and 1962 observations were made on the activities of predators of the pear psylla, Psylla pyricola Förster, in the Okanagan Valley of British Columbia. Attacking the psylla together, the anthocorid bug, Anthocoris melanocerus Reuter, and the green lacewing, Chrysopa oculata Say, gave more effective suppression than either predator alone. DDT and Diazinon drastically reduced numbers of these predators b commercial plantings. In non-sprayed, isolated orchards, trace numbers of these predators maintained effective control of pear psylla populations.

Anthocoris dimorphicus n. sp. is described and characters are given to distinguish it from A. musculus (Say). Two species, A. confusus Reut. and nemoralis (F.) are recorded for the first time from North America. A. antevolens White, a common species in western North America, is recorded from Ontario, collected in association with galls of Pemphigini aphids on Populus spp.

The life history and habits of Eucordylea ducharmei, a gelechiid needle-miner on spruce, are described along with short notes on some of its parasites.